Showing papers by "Carlos Roberto Ribeiro de Carvalho published in 2003"

Prevalence rates of infection in intensive care units of a tertiary teaching hospital

Abstract: OBJECTIVE: To determine the prevalence rates of infections among intensive care unit patients, the predominant infecting organisms, and their resistance patterns. To identify the related factors for intensive care unit-acquired infection and mortality rates. DESIGN: A 1-day point-prevalence study. SETTING:A total of 19 intensive care units at the Hospital das Clinicas - University of Sao Paulo, School of Medicine (HC-FMUSP), a teaching and tertiary hospital, were eligible to participate in the study. PATIENTS: All patients over 16 years old occupying an intensive care unit bed over a 24-hour period. The 19 intensive care unit s provided 126 patient case reports. MAIN OUTCOME MEASURES: Rates of infection, antimicrobial use, microbiological isolates resistance patterns, potential related factors for intensive care unit-acquired infection, and death rates. RESULTS: A total of 126 patients were studied. Eighty-seven patients (69%) received antimicrobials on the day of study, 72 (57%) for treatment, and 15 (12%) for prophylaxis. Community-acquired infection occurred in 15 patients (20.8%), non- intensive care unit nosocomial infection in 24 (33.3%), and intensive care unit-acquired infection in 22 patients (30.6%). Eleven patients (15.3%) had no defined type. The most frequently reported infections were respiratory (58.5%). The most frequently isolated bacteria were Enterobacteriaceae (33.8%), Pseudomonas aeruginosa (26.4%), and Staphylococcus aureus (16.9%; [100% resistant to methicillin]). Multivariate regression analysis revealed 3 risk factors for intensive care unit-acquired infection: age > 60 years (p = 0.007), use of a nasogastric tube (p = 0.017), and postoperative status (p = 0.017). At the end of 4 weeks, overall mortality was 28.8%. Patients with infection had a mortality rate of 34.7%. There was no difference between mortality rates for infected and noninfected patients (p=0.088). CONCLUSION: The rate of nosocomial infection is high in intensive care unit patients, especially for respiratory infections. The predominant bacteria were Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus (resistant organisms). Factors such as nasogastric intubation, postoperative status, and age ³60 years were significantly associated with infection. This study documents the clinical impression that prevalence rates of intensive care unit-acquired infections are high and suggests that preventive measures are important for reducing the occurrence of infection in critically ill patients.

Lung recruitment maneuvers in acute respiratory distress syndrome.

Abstract: In the experimental setting, repeated derecruitments of the lungs of ARDS models accentuate lung injury during mechanical ventilation, whereas open lung concept strategies can attenuate the injury. In the clinical setting, recruitment manuevers that use a continuous positive airway pressure of 40 cmH2O for 40 secs improve oxygenation in patients with early ARDS who do not have an impairment in the chest wall. High intermittent positive end-expiratory pressure (PEEP), intermitent sighs, or high-pressure controlled ventilation improves short-term oxygenation in ARDS patients. Both conventional and electrical impedance thoracictomography studies at the clinical setting indicate that high PEEP associated with low levels of pressure control ventilation recruit the collapsed portions of the ARDS lungs and that adequate PEEP levels are necessary to keep the ARDS lungs opened allowing a more homogenous ventilation. High PEEP/low tidal volume ventilation was seen to reduce inflammatory mediators in both bronchoalveolar lavage and plasma, compared to low PEEP/high tidal volume ventilation, after 36 hours of mechanical ventilation in ARDS patients. Recruitment maneuvers that used continuous positive airway pressure levels of 35-40 cmH2O for 40 secs, with PEEP set at 2 cmH2O above the lower inflection point of the pressure-volume curve, and tidal volume < 6 mL/kg were associated with a 28-day intensive care unit survival rate of 62%. This contrasted with a survival rate of only 29% with conventional ventilation (defined as the lowest PEEP for acceptable oxygenation without hemodynamic impairment with a tidal volume of 12 mL/kg), without recruitment manuevers (number needed to treat = 3; p < 0.001). In the near future, thoracic computed tomography associated with high-performance monitoring of regional ventilation may be used at the bedside to determine the optimal mechanical ventilation of the ARDS keeping an opened lung with a homogenous ventilation.

The soybean sucrose binding protein gene family: genomic organization, gene copy number and tissue‐specific expression of the SBP2 promoter

Abstract: The sucrose binding protein (SBP) from soybean has been implicated as an important component of the sucrose uptake system. Two SBP genomic clones, gsS641.1 and gsS641.2, which correspond to allelic forms of the GmSBP2/S64 gene, have been isolated and characterized. As a member of the seed storage protein superfamily, it has been shown that the SBP gene structure is similar to vicilin genes with intron/ exon boundaries at conserved positions. Fluorescence in situ hybridization (FISH) suggested that the soybean SBP gene family is represented by at least two non-allelic genes corresponding to the previously isolated GmSBP1 and GmSBP2/S64 cDNAs. These two cDNAs share extensive sequence similarity but are located at different loci in the soybean genome. To investigate transcriptional activation of the GmSBP2 gene, 2 kb 5¢-flanking sequences of gsS641.1 and gsS641.2 were fused to the b-glucuronidase (GUS) reporter gene and to the green fluorescent protein (GFP) reporter gene and independently introduced into Nicotiana tabacum by Agrobacterium tumefaciens-mediated transformation. The SBP2 promoter directed expression of both GUS and GFP reporter genes with high specificity to the phloem of leaves, stems and roots. Thus, the overall pattern of SBP‐GUS or SBP‐GFP expression is consistent with the involvement of SBP in sucrose translocation-dependent physiological processes.

Síndrome pulmonar e cardiovascular por hantavírus

Abstract: A sindrome pulmonar e cardiovascular por hantavirus e uma doenca de conhecimento relativamente recente e frequentemente fatal, apresentando-se como sindrome do desconforto respiratorio agudo. No Brasil, desde o primeiro surto, relatado em novembro/dezembro de 1993, em Juquitiba, 226 casos ja foram registrados pela Fundacao Nacional da Saude. A doenca afeta individuos previamente higidos, apresentando-se com prodromo febril e sintomas semelhantes aos de um resfriado comum, podendo rapidamente evoluir para edema pulmonar, insuficiencia respiratoria aguda e choque. A hemoconcentracao e a plaquetopenia sao comuns da sindrome pulmonar e cardiovascular por hantavirus, e o quadro radiologico tipico e de um infiltrado intersticial bilateral difuso, que progride rapidamente para consolidacoes alveolares, paralelamente a piora do quadro clinico. A mortalidade inicial era em torno de 75% e declinou para aproximadamente 35%, nos ultimos anos. Os pacientes que sobrevivem geralmente recuperam-se completamente, cerca de uma semana apos o estabelecimento do quadro respiratorio. O agente causal, nao reconhecido ate ha pouco, foi identificado como um hantavirus, cujo reservatorio natural sao animais roedores da familia Muridae, subfamilia Sigmodontinae. O tratamento especifico antiviral ainda nao e bem estabelecido, estando em estudo a eficacia de ribavirina. Cuidados de terapia intensiva como ventilacao mecânica e monitoramento hemodinâmico invasivo sao necessarios nas formas mais graves da doenca. Essas medidas, se instituidas precocemente, podem melhorar o prognostico e a sobrevida dos pacientes com sindrome pulmonar e cardiovascular por hantavirus.

Hemorragia alveolar associada a nefrite lúpica

Abstract: Alveolar hemorrhage leading to respiratory failure is un-common. Various etiologies have been reported, includ-ing systemic lupus erythematosus, which generally pre-sents as pulmonary-renal syndrome. It is believed that thepathogenesis of microangiopathy is related to deposits ofimmune complexes that lead to activation of cellular apo-ptosis. The authors report two cases of alveolar hemor-rhage and respiratory failure, both requiring mechanicalventilation. The two cases had opposite outcomes afterpharmacological therapy. The presence of anti-glomeru-lar basement membrane antibodies in one of the casesdemonstrates the multiplicity of physiopathological mech-anisms that may be involved. This multiplicity of mecha-nisms provides a possible explanation for the heteroge-neous responses to the available treatments.Hemorragia alveolar, como causa de insuficiencia respi-ratoria, e pouco frequente, com diversas etiologias possi-veis. Entre elas, o lupus eritematoso sistemico, que seapresenta geralmente como sindrome pulmao-rim, pos-sui alta morbimortalidade. Acredita-se que a patogeneseda microangiopatia, tanto renal como pulmonar, estejaassociada ao deposito de imunocomplexos, que ativariamas vias de apoptose celular. Relatam-se dois casos de pa-cientes com nefrite lupica que evoluiram com hemorragiaalveolar associada a insuficiencia respiratoria necessitan-do de ventilacao mecânica com evolucoes totalmente dis-tintas frente as terapias farmacologicas. O achado de an-ticorpos antimembrana basal em um dos casos evidenciaa multiplicidade de mecanismos fisiopatologicos possivel-mente envolvidos, que poderiam justificar as respostasheterogeneas frente aos tratamentos disponiveis.